Llama anti-human fibrinogen

Anti-human fibrinogen
Antibody against fibrinogen (coagulation factor I), a glycoprotein complex that circulates in the blood of vertebrates. It consists as a dimer of 3 pairs of non-identical chains, Aα, Bβ and γ, which are cross-linked by disulfide bonds in their N-terminal segments. Additionally, the molecule has 2 terminal D domains and one central E domain. Fibrinogen circulates as a soluble plasma glycoprotein with a typical molecular weight of ~340 kDa. The normal concentration of fibrinogen in blood plasma is 150 - 400 mg/dL. Fibrinogen has a circulating half-life of ~4 days. During tissue and vascular injury, fibrinogen is converted enzymatically by thrombin to form individual fibrin strands by attacking the N-terminus of the Aα and Bβ chains. The individual fibrin strands polymerize and are crosslinked by blood coagulation factor XIIIa to form an extensive interconnected fibrin network, which forms the basis for the formation of a mature fibrin clot. In addition to forming fibrin, fibrinogen also functions as a bridge between blood platelets through binding to integrin αIIbβ3 (also termed glycoprotein GPIIbIIIa), the surface-expressed fibrinogen receptor. Moreover, fibrinogen and/or fibrin mediate blood platelet and endothelial cell spreading, tissue fibroblast proliferation, capillary tube formation, and angiogenesis and thereby promote revascularization and wound healing. Fibrinogen is an acute-phase protein, meaning that its blood levels rise in response to systemic inflammation, tissue injury, and certain other events, including pregnancy. It is also elevated in various cancers. Elevated levels of fibrinogen in inflammation as well as cancer and other conditions have been suggested to be the cause of thrombosis and vascular injury that accompanies these conditions. Reduced levels and/or dysfunctional fibrinogen occur in various congenital and acquired human fibrinogen-related disorders, representing a group of rare conditions in which individuals may present with severe episodes of pathological bleeding and thrombosis.